PSI - Issue 18

A. Tridello et al. / Procedia Structural Integrity 18 (2019) 314–321 Author name / Structural Integrity Procedia 00 (2019) 000 – 000 associated to surface defects was larger than the SIF threshold, thus justifying the fatigue failure range below 2 ∙ 10 6 cycles for almost all the specimens showing a surface failure. In conclusion, the experimental results confirmed that for the tested specimens, not machined and subjected to a manual polishing, surface defects control the VHCF response: if the surface defects are removed through a post treatment process, the crack origin more likely shifts to internal defects, yielding a significantly larger fatigue life and a consequent enhancement of the VHCF response. References 321 8 Edwards, P., Ramulu, M., 2014. Fatigue performance evaluation of selective laser melted Ti–6Al–4V. 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